31P Magnetic Resonance Spectroscopic Imaging Reflects Metabolic Features of Hepatocellular Carcinoma and Their Correlations with Tumor Aggressiveness

Purpose To investigate whether ³¹ P two-dimensional magnetic resonance spectroscopic imaging ( ³¹ P-2D-MRSI) could noninvasively reflect HCC metabolic features and to evaluate their correlation with tumor aggressiveness. Methods This prospective study classified patients with HCC into early-stage [Barcelona Clinic Liver Cancer (BCLC) 0/A] and advanced-stage (BCLC B/C). Phospholipid metabolism ratios were obtained from lesion and background voxels using ³¹ P-2D-MRSI, respectively. Patients were further stratified by Ki-67 expression (early-stage) or treatment-response to chemotherapy (advanced-stage). Significant differences in the ratios were assessed using independent-samples t test or Mann–Whitney U test. Results When comparing all HCC lesions (n = 44) with background tissue (n = 37) and, within lesions, advanced-stage (n = 21) with early-stage tumors (n = 23), both analyses showed higher mean PME/PDE (0.91 vs 0.50; 1.41 vs 0.71, all p < 0.017) and PE/PDE (0.50 vs 0.28; 0.73 vs 0.40) ratios in lesions and advanced-stage tumors. In early-stage HCCs, high Ki-67 expression lesions (> 20%, n = 10) exhibited higher mean PME/PDE and PE/PDE (0.73 vs. 0.51; 0.44 vs. 0.27) ratios than low Ki-67 expression lesions (£ 20%, n = 13). However, within advanced-stage HCCs, non-responding lesions (n = 13) showed lower mean PME/PDE and PE/PDE ratios (1.05 vs. 2.19; 0.63 vs. 1.02) than responding lesions (n = 8). Conclusion ³¹ P-2D-MRSI may stratify HCC aggressiveness by metabolic ratios.